A young woman collapses in front of a bus after a free concert ends with the police practicing crowd control and ending the concert. At first glance it appeared that the non lethal methods that the police practice may have backfired until upon closer inspection at the autopsy, Hammerback noticed discoloration on her face masked by makeup. It turned out to be radiation, and the girl died from radiation poisoning. The question marks on the how and why get underlined when a second body with the same cause of death shows up, and someone makes a very public announcement that there was a third victim.
It was an interesting case with a few nice little twists. I did have a good guess as to who was behind it when he first showed up in the episode though. I also liked the moment at the end with the guys visiting Hammerback, though why wasn't Danny or Adam invited. Still waiting for the resolution of last season's personal drama, but other than that I liked it.